Improvement in low-water detectors for boilers



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THOMAS' BUTTON, OF PORT JERVIS, NEW YORK, ASSIGNOR TO HIMSELF AND THOMAS MAGUIRE, OF SAME PLAGE.

Laim Patent No. 81,989, dated 4stemma. s, r1868.

IMPROVEMENT IN'LOW-WATER- DETEGTORS FOR BOILERS.

TO ALL WHOM IT `MAY CONGERN:

Be it known thnt I, THOMAS DUTTON, of Port Jervis, in the county of Orange, and State of New York, have invented a certain new and useful Improvement on Low-Water Detectors for Steam-Boilers; and I do hereby declare that the following is a. full, clear, and exact description of the same, reference beinghad to the accompanying drawings, and to the letters and marks thereon, which said drawingsform part of this specification, and show my invention applied to the 'crown-sheet of a. boiler- Figure 1 being a top view thereof,

Figure 2 a view by vertical section on th'ered line of iig. I, and

Figure 3 being a bottom view'.

In each of these figures like parts are designated by like marks and letters.

My invention relates to that class of detectors where plugs of fusible metals or fusible alloys are used'; and myinven-tion consists in the construction of the plugs and their receptacle, as hereinafter set forth.

Fig. 2 of the drawings shows a. plug, a, made of brass, screwed into the crown-sheet 6 the centralv hole of the plug being unfilledwith metal to show the screw-thread and countersink the other holes are filled withthe fusible metal. It is preferable to make theplug of brass, on account 4offits getting hot quick, and not corrod ing, so that the plug can easily be removed whenever it may be desirable to refill the holes, or for any other purpose. The holes should be-tinned before the fusible metal or alloy is run in, to make a better adhesion of` the alloy or metal to the surface of the hole. By having the hole threaded and countersunk, the metal will be less likely to be forced out by the pressure of the steam, than'whenA the holes. are plain or not countersunk.

This plug is, as shown by fig. 2, so far above the crown-sheet that the fusible metal will be melted by the excessive or undue heat before the crown-sheet has become entirely exposed and uncovered by water'.

It will be noticed that the plug is bell-mouthed, thus allowing the flame and heat free'access to the interior` of the plug, which interior forms ahrc-chamber above the crown-sheet of the fire-box on the plate of the boiler. This interior surface is six-sided, as is also tbe ange c, so that the plug may be screwed in or out by a bar or by a wrench.

Whatlf claim as my invention, and desire to secure by Letters Patent, is-

The construction of the plug a, substantially as herein set forth.

This specification signed, this 2d day of January, 1868.

THOMAS DUTTON. Witnesses:

FRANcIs MAnvxN,

ROBERT N. Tommy. 

